Safety clutch mechanism



May 26, 1925.

C. A. SAWYER, JR

SAFETY CLUTCH MEGHANISM Filed April 9, 1921 2 @lewis-Sheet 1 JMay 26, 1925. I l 1,539,430

l`C A. SAWYER, JR

SAFETY CLUTCH MECHANISM 2 Sheets-Sheet 2 Patented May 25, 1925.

UNITED STATES CHARLES ADRIAN sAWrEAR., AJR., or NEWTON, MASSACHUSETTS.

SAFETY CLUTCH MECHANISM. 1

yApplication led April 9,

l 10 all 'whom it may concern.

Be it known that I, CHARLES ADRIAN SAwYnn, Jr., a citizen of the United States, and resident of Newton, in the county of Middlesex and State of Massachusetts, have invented an Improvement in Safety Clutch Mechanisms, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings represent-ing like parts.

My present invention relates to clutching devices, and more particularly to an improved safety clutching device applicable for use in punch presses, stamping machines and the like.

In punching or stamping machines adapted for continuous operation, and in` which material is continuously fed into position beneath, or in aline-ment with, operating tools, suoli as cutters, it is kdesirable that means be pro-vided for preventing possible injury to the operating tools, and even the machine itself, should the various parts of the machine fail to function properly and in synchronism. In my development of the leather cutting art, particularly the rapid and economical blanking out o-f shoe sole blanks, I have devised a machine in which strips of sole leather are continuously fed beneath a reciprocating cutter head, the blanking out of the shoe sole blanks being an automatic continuous operation. This machine forms the subject matter of my copending application Ser. No. 492,908, filed Aug. 17, 1921, and while such machine oper- `ates perfectly to produce the desired results, the capital invested is too great to warrant the risk of injury should the various elements thereof fail to function in synchronism. As the greatest risk is the injury to the expensive cutters, I have devised means for automatically operating the clutching mechanism to disconnect tlhe operating mechanism of the machine from the power transmitting devices should the machine fail to function properly. I prefer to have such means constantly in action, to perform their function should this be necessary, and to be practically under the control of those portions of the machine that are likely to cause damage to the machine. To this end,-I control the positioning of the clutch operating mechanism by means operated by the material moving bars.

An object of my invention is an improved safety clutch operating mechanism.

1921, serial N0. 460,117.

Another object is ran impro/ved safety clutch operating mechanism controlled in its action by a movable portion of the machine to which the clutch is applied.

Still another object is an improved .clutch operating mechanism movable into and out construction and arrangement, of parts will .appear las the description of the invention progresses.

In the accompanying drawings, illustrating the prefer-red embodiment of my invention,

Fig. tion, l

Fig. 2 is an end elevation, looking from the left inFig. 1, and partly in section, and

Fig. 3 is a detail plan view, partly in section, showing the clutch operating mecha- 1 is a longitudinal sectional eleva- Referring tothe drawings, 10 designates albase of a leather cutting machine, such 4as that described and claimed in my copending application, Ser No. 492,908, filed Aug. 17,

1921, towhich my invention has been applied.- On this base 10 ismounted standards or uprights 11 spacedv apart and held in position by bars 12. Y Intermediate `the ends Vof the standardsl 11 is a bed 13 on which is are tied together by a cross-plate 16.- A -i shaft 18 mounted-.in suitable bearings on vthe standards 11, is provided at one end lwith a rotatable pulley 19, fly wheel 20 and one member 21 of a clutch. Slidably mounted on, but rotatable with, the shaft 18 is 'another member 22 ofthe clutch, and provision is made for bringing the members 21 .and 22 into and out of engagement with each, other to control the operationof the shaft 18. Intermediate the ends of the shaft 18 are secured the spur gears 23, which mesh with the gears 24' mounted on the rotatable shaft 25 in the Standards 11. Through suitable connectionsl between the l rods 82 are rotatably mounted on the shaft 83 securedV in thecrosshead 14.

Bearing vbrackets 26, attached 'to either side of .the bed 13, have rotatably mounted therein la shaft 27, At @the rear .ot said shaft, or at the right hand side of Fig. V1, is securely fastened `a .clutch operating fork ,28 which ,cooperates with a groove 29 in fa member y,30 `slidably lmounted on a shaft 31, mounted on the standards'll said mem: ber .30 being associated With the clutch member 22. At the Afront 'end of the shaft 27 is secured a crank arm 32, to the free endof which is pivotally attached one end .of aconnecting rod 33, the other end of which is pivotally l-attached to the free end of a crank arm 34, secured to a shaft rotatably mounted in bearingbracltets 36 on one ofthe standards f 11.k Slidablyl vmounted V- in the standards 11, and parallel to the shaft i25^is a ,rod 37, provided near one end With a V.stop v38 which engages with one v `of the standards llvto limit the movement of said rodto the right, as viewed inv Fig. Near the other end of the rod 37 is a stop 39 and on the Irod andbetvveen t-his sto ,and the Astandard 11 to the left of the mac ,-ine, as viewed in Fig.y

2 is a coil spring 4G, which tends to force the 1=od39 to `the right.v Adjustably mounted by setscrew 141 on the rod 37 is a' block 41 carrying a pin or rod -42 which extends rearwardly of the machine and cooperates with a circular groove 44 in a roller 45, rotatably/mounted on a stub shaft 46 secured to the shaft 27. AsV shown in Fig. 2, .this roller lies slightly to the right .of the cam .47 secured Yto the shaft 25. There is anoperati-ng handle (not shown) secured to the shaft 35 and positioned Within easy and convenient reach of the operator, Whol stands `atfthe front of vthe machine, or at the eX- treme left of Fig. 1. By means of this handle (not shown), clutching mechanism above described may be controlledby the opera-tor. Mounted `on .the'base 10, at vthe front of the standards 11, `are frame members 49 spaced apart and held in position by reds 50 Avvfh-ile on the base and at ythe rear of the standards 11 is a rframe 51. In the frames 49 and 51 are shafts carrying a'plurali'ty of sprockets 52 over which .run chains 53, vthese chains being connected together V:and 'spaced 'apart b a plural-ity of cross bars 54 but 'one ofwvhicli is shown, whichJ chains 59. A shaft 6() in the frame 49 has pivotally mounted therein aframe carrying at its upper end` a shaft 62. At each Aend ofthe air'of the sprockets 52,

shaft 62 is secu-red a crank 63 having pivotally mount-ed at its free end a connecting l rod 64a.

The side members of the `frame 58 are each i provided, on their inner face With aggroove 64 in which is mounted `a push bar Y65V Ycarrying members (not shown) which successively engage the cross bars54 to feed the chains 53 forward step by step. vrhe vaf rious operating partspabove described are so ,proportioned and positioned with rela,-l

tion toeach other as Vto cause the cross 'bars 54 to bring sheets of leather 56-into position i beneath'the cross head 14'andgremove the same therefrom atthel proper tii'ne- The operator, therefore, by preperlymanipulatf ing'the handle (notshown) brings the clutch members 21 and -22 into engagement with each-other, andthe farther action of themachine is automatic, his yonly duty thereafter being to feed Strips of leather 56`tol the-de- Y vice.

It may happen, however, that the onward movement of the c'ross'bars'54 andthe downward movement of the-cutter head 15 Wil not be Vin Lsynchronism, andunder these circumstancesthere is grave danger ofV serious injury to the machine. To guard Yagainst this contingency', I-provide on the side members offthe frame '58, bars 66, and onsaid bars I pivetally moun-t at 161 a pair of bell crank levers 67, to one arm of each I pivot- `ally attach-a connectingl rod 68, While tothe Y Aotherarm of'ea'eh lever 67 I pivotallyattach,

atv169 a seoondconnecting rod 69 equal in length to thelength of the connecting rod 68, and formed on the bottom of each connecting rod 69 is a shoe 70 beveled at its forwaird end and slightly greater in length than the Width of the cutting-block. As the cross -bars'54 movealong-the frame 58, they engagethe bevel atthe front end of the shoes g 70, movingthe connecting rod l69'upwardly, and keeping it 'in f its uppermost Vposition until the cross bars 54 move beyond the rear end. ofsuch ,shoes 70, when suchV shoes and connecting rods fall by their own Weight into 'the connecting rod 69, While the lother arm 73 extends downward intopositicn to eng-age with the spring pressed rod 37, heretofore described. Assuming that the machine is in operation, and that the leather sheets or strips 56 are fed successively beneath the cutter head l5 to be cut into sections, such as shoe sole blanks, it will be obvious that as the cross bar 54 comes into engagement with the bevel on the shoe 70, the connecting rod 69 will be raised, raising the arm 72 of the bell crank lever about the pivot point in the bearing bracket 7l and moving the free end of the arm 73 to the left, as viewed in Fig. 2, against the spring pressed rod 37, thus moving the rod 42 to the left and causing a movement to the left of the roller 45 into the path of movement of the cam 47, attached to the shaft 25. This cam 47 is so positioned on the shaft 25 with relation to the reciprocating movement of the critter head 15 and the movement of the chains 53 that assuming the cutter head l5 and chains 53 to be moving in synchronism, the roller 45 will move out of the path of movement of the cam 47 by the movement of the cross bar 54 past the shoe 70 at the proper instant and the consequent movement to the right, as viewed in Fig. 2, of the spring pressed rod 37. The clutching mechanism, therefore, will be held in operative position as long as the cross bars 54 come successively into and out of position. If, however, one of the cross bars 54 over-runs when coming into position with respect to the critter head 15, or does not move far enough when the cutting operation is completed, the end of the arm 72 will remain raised and the roller 45 held in position in the path of the cam 47. The cam 47, engaging the roller 45, rotates the shaft 27, and by means `of the clutch fork 28 disengages the clutch members 2l and 22 to stop the rotation of the shaft 25 and thus prevent downward movement of the cutter head l5, and possible injury to the cutters carried thereby by reason of their engagement with the cross bar.

As long, therefore, as the machine is operating properly, the safety clutch operating mechanism will not Voperate to stop the machine, but is always in position t0 do so, moving into such position at every stroke of the cutter head, and out of such position again if its services are not required. When its services are required, its action is positive and no damage can result to the machine.

As my improved device was developed for use with a leather cutting machine, such as described and claimed in my copending application, Ser. No. 492,908, above referred to, I have, in this application, described it in connection with such a machine, but as the' device is capable of being used as a safety device for general machine use, I desire to claim it broadly. While I have described the construction of my device somewhat in detail, it is to be understood that I may vary the size, shape and arrangement of parts constituting thel same within wide limits without departing from the spirit of the invention. i

My invention is further described and vdefined in the form of claims as follows:

l. An improved clutch operating mechanism comprising a rotatable shaft,ka cam thereon, a clutch for connecting said shaft to a source of power, clutch operating means, a stub shaft connected thereto, a Yroller slidably and rotatably mounted on said stub shaft, and means for moving said roller into and out of the path of movement of said cam at predetermined times.

2. An improved clutch operating mechanism comprising a rotatable shaft, a cam thereon, a clutch for connecting said shaft t0 a source of power, clutch operating means, a stub shaft connected thereto, a roller slidably and rotatably mounted on said stub shaft, a slidable shaft connected to said roller, and controlling the slidable movement thereof for moving the same into and out of the path of movement of said cam at predetermined times.

, 3. An improved clutch operating mechanism comprising a rotatable shaft, a cam thereon, a clutch for connecting said shaft to a source of power, clutch operating means, a stub shaft connected thereto, a roller slidably and rotatably mounted on said stub shaft, a slidable shaft connected to ysaid roller and pivotally mounted means controlling the movement of said slidable shaft to move said roller into and out of the path of movement of said cam at predetermined times.

4. An improved clutch operating mechanism comprising a rotatable shaft, a cam thereon, a clutch for connecting said shaft to a source of power, clutch operating means, a stub shaft connected thereto, a roller slidably and rotatably mounted on said stub shaft, a slidable shaft connected to said roller, pivotally mounted means controlling the movement of said slidable shaft 'to move said roller into and out of the path of movement of said cam at predetermined times, and means for controlling the pivotally mounted means.

In testimony whereof, I have signed my name to this specification.

CHARLES ADRIAN SAVYER, Jn. 

